Deicing means for aircraft



' March 31, 1942. F. G. MARSHALL T2373,206

DEICING MEANS FOR AIRCRAFT Filed April 28, 1941 2 Sheets- Sheet 1 March 31, 1942. F, G, MARgHALL 2,278,206

DEICINGVZMEANS' FOR AIRCRAFT Filed April 28, 1941 2 Sheets-Sheet 2 143872507 ll fmdmLd J M011- [1 6M am Patented Mar. 31, 1942 DEICING MEANS FOR AIRCRAFT Frederick George Marshall, Leamington Spa, England, assignor to Constant Speed Airscrcws Limited, Warwick, England Application April 28, 1941, Serial No. 390,827 In Great'Britain February 27, 1940 Claims.

This invention relates to de-icing means for aircraft having adjustable pitch propellers and has for its object to provide an improved arrangement for controlling the delivery of the de-icing liquid at the required times.

According to the present invention delivery of liquid under pressure for de-ieing purposes on aircraft is'controlled by adjustment of the pitch angle of the blades of the propeller.

The invention involves the use of one or more valves carried bya part, such as the spinner,

which rotates with the propeller.

The valve or each valve may be operated by a cam or projection on a blade of the propeller either directly or indirectly, as by means of a lever.

The de-icing liquid may be supplied to the valve or valves from a container formed in the spinner so that when the valve or valves is or are opened the liquid is delivered under pressure by the centrifugal force created by the rotation of the container. Alternatively, the supply of deicing liquid may be obtained from a stationary container by means of a pump.

The delivery of the de-icing liquid may be arranged to take place through a plurality of holes in the spinner, said holes being open to the delivery side of the valve or valves.

In the accompanying drawings,

Figure 1 is a longitudinal sectional view through the spinner of an airscrew illustrating one way of carrying out the present invention.

Figure 2 is a plan view thereof, and

Figure 3 is a detail view of the valve and propeller blade.

Referring to the arrangement shownin the drawings, 2 represents one of the blades of an adjustable pitch propeller for aircraft and 3 the usual spinner which encloses the hub of the propeller and rotates therewith.

The nose of the spinner is formed with double walls to provide a container! for the de-icing liquid in bulk and is provided with a filling oriflce closed by means of a removable plug 5.

A valve 6 which may be of the spring-loaded plunger type, shown more clearly in Figure 3, is fixed to the inside wall of the spinner between .the container 4 and a blade 2 of the airscrew and has an inlet connection 1 in open communication with the container and an outlet port 8 communicating with a trough 9 fixed to the inside wall of the spinner below a series of open delivery holes lll formed in the latter in front of the blade 2.

The outlet port 8 of the valve is normally closed by the valve plunger I I under the influence of its spring [2, and is arranged to be opened by adjusting the pitch angle of the blade of the propeller. For this purpose the root of the blade is provided wtih a clip l3 firmly'securcd thereto by a bolt l4 and the spinner is fitted with a lever one arm i5 of which is connected with the valve plunger H whilst the other arm 56 bears against the head of the bolt I l.

The type of variable pitch propeller employed is one that is controlled from the cockpit and the arrangement is such that when the pilot is aware that ice is forming on the machine he can open the valve for the delivery of de-icing liquid by adjusting the pitch angle of the blades of the propeller from the maximum cruising position, indicated by the dotted centre line aa in Figure 3, in the direction of the feathering position through an angle of about 5 to the angular position represented in dotted lines in the same figure. This movement is transmitted by the lever to the valve plunger which is-thereby caused to uncover the outlet port 8 whereupon de-icing liquid under pressure is sprayed through the holes l0 over the propeller blades and other parts of the aircraft.

I claim:

1. In aircraft the combination with a variable pitch propeller and with a source of supply, of a de-icing liquid of valves for controlling the distri bution of said liquid over the machine and means responsive to adjustment of the pitch angle of the blades of said propeller for opening and closing said valves.

2. In aircraft the combination with a variable pitch propeller and with a container for de-icing liquid rotating therewith, of valves for controlling the distribution of said liquid over the machine and means responsive to adjustment of the pitch angle of the blades of said propeller for opening and closing said valves.

3. In aircraft the combination with a variable pitch propeller and with a spinner rotating therewith, of a container for de-icing liquid carried by said spinner and means responsive to adjustment of the blades of said propeller for controlling the distribution of said liquid over the machine.

4. In aircraft the combination with a variable pitch propeller and with a spinner rotating therewith, of a container for de-icing liquid carried by said spinner, valves for controlling the distribution of said liquid over the machine and means responsive to adjustment of the pitch angle of the blades of said propeller for opening and closing said valves. 

